After 50 years of research, scientists have yet to build a robot that can learn to manipulate new objects as proficiently as a one-year-old child. Robots don't react well to new situations; most of their movements must be programmed in advance. Some use sensors to fine-tune their movements in real time, but they generally don't retain and interpret the sensor data. So while they might navigate a room without bumping into things, they can't stop to help rearrange the furniture.

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